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ABSTRACT Wind‐driven sediment transport drives significant landscape evolution in arid regions. Wind‐blown sand can form large dunes, or can erode exposed surfaces via abrasion. Previous works on aeolian abrasion have focused on the geomorphological features resulting from abrasion (for example, ventifacts and yardangs) through both field and wind‐tunnel experiments. However, relatively little attention has been given to how abrasion varies spatially as sand flux converges on a sand sink, such as a dune field. This work studied an arid landscape using field measurements and collected weather data to quantitatively measure how abrasion varies in space around the Ibex Dune Field. From March 2021 to October 2022, the wind conditions at two separate locations in the region were monitored, saltating sand flux was captured using fully rotating sediment traps, ventifacts were mapped along several transects, and abrasion‐related mass loss on mounted gypsum plaster samples was measured. These results suggest that the magnitude of abrasion is approximately inversely proportional to the distance away from the dune field, increasing in magnitude as sands converge and fluxes increase at the dune field sink. Comparison between modern winds and ventifact orientations suggests that additional complexity, not aeolian processes alone, may be shaping the morphology of surface cobbles. [ABSTRACT FROM AUTHOR]

Many planetary surfaces have been shaped by eolian and fluvial processes, and understanding the resulting landscape is of critical importance to understanding changes in climate. Surface features on Earth and Mars are commonly observed using a variety of remote sensing methods. The observed geomorphology provides evidence of present processes and paleo-processes, but interpretations are limited by the resolution of the data and similarity to well-understood systems on Earth. In this work, we study a complex fluvio-lacustrine and eolian landscape at Deep Springs playa, California, using field measurements and remote sensing as an analog for a wet-to-dry-transitioning landscape on Mars. The playa system in arid Deep Springs reflects fluvio-lacustrine processes in its interior but transitions to eolian-dominated processes along the playa margin. Weather station data and field observations collected over 34 months illustrate the interplay between eolian and lacustrine processes and provide context for interpreting the observed geomorphology in aerial images. Our results showed a consistent distal-to-proximal geomorphic transition in the landscape defined by the changing expression of polygonal fractures, wave ripples, and evaporite deposits. Crescent-shaped sedimentary deposits, originally suspected to be related to barchan dunes, proved unrelated to eolian processes. We discuss the processes, sedimentary features, and climate drivers at Deep Springs to provide a potential framework for identifying and interpreting similar interactions between fluvio-lacustrine and eolian geomorphology elsewhere on Earth, on Mars, and beyond. [ABSTRACT FROM AUTHOR]

Many planetary surfaces have been shaped by aeolian and fluvial processes, and understanding the resulting landscape is of critical importance to understanding changes in climate. Surface features on Earth and Mars are commonly observed using a variety of remote sensing methods. The observed geomorphology provides evidence of present- and paleo-processes, but interpretations are limited by the resolution of the data and similarity to well-understood systems on Earth. In this work, we study a complex fluvio-lacustrine and aeolian landscape at Deep Springs playa, California, using field measurements and remote sensing as an analog for a wet-to-dry transitioning landscape on Mars. The playa system in arid Deep Springs reflects fluvio-lacustrine processes in its interior, but transitions to aeolian-dominated processes along the playa margin. Weather station data and field observations collected over 34 months illustrate the interplay between aeolian and lacustrine processes and provide context for interpreting the observed geomorphology in aerial images. Our results showed a consistent distal-to-proximal geomorphic transition in the landscape defined by the changing expression of polygonal fractures, wave ripples, and evaporite deposits. Crescent shaped sedimentary deposits, originally suspected to be related to barchan dunes, proved unrelated to aeolian processes. We discuss the processes, sedimentary features, and climate drivers at Deep Springs to provide a potential framework for identifying and interpreting similar interactions between fluvio‐lacustrine and aeolian geomorphology elsewhere on Earth, on Mars, and beyond. [ABSTRACT FROM AUTHOR]

Layered deposits occur on Mars in a wide variety of settings and morphologies, including inside craters as large mounds. Many origins have been proposed for these intracrater layered deposits, but recent work has suggested the possibility of deposition by ancient aeolian dunes. Distinguishing dune deposits requires identifying cross-strata which may not be resolvable even with the highest spatial resolution imaging of Mars. In this work, we employ an alternative method and attempt to eliminate the possibility of aeolian deposition by comparing martian layer geometries to the angles and thicknesses of aeolian sets on Earth. Layering in Henry crater falls within the expected bounds for aeolian strata, and if ancient dunes deposited these layers, then the sets record the passage of dunes with 10-100 m spacing that were generally migrating toward the center of the crater. The Henry crater mound comprises ~8000 km³ of sediment, and if all layers reflect dune deposition, we estimate mound deposition would then take at least ~0.5 m.y. As a whole, ~20,000 km³ of sediment are preserved in intra-crater layered deposits in Arabia Terra. Results from this case study of Henry crater suggest that at least some of this volume may be from aeolian dunes, in which case intra-crater layered mounds may host an untapped record of very ancient martian aeolian activity. [ABSTRACT FROM AUTHOR]